Dumbbell



FIG. 1 is a front view of a dumbbell;

FIG. 2 is a first lateral view of the dumbbell of FIG. 1;

FIG. 3 is a top view of the dumbbell of FIG. 1;

FIG. 4 is a bottom view of dumbbell of FIG. 1; and,

FIG. 5 is a front perspective view of the dumbbell of FIG. 1. 

CLAIM I claim the ornamental design of a dumbbell, as shown. 